Bag tie dispenser

ABSTRACT

An apparatus that cuts a strip of plastic film from a length of film advanced by a film metering device, applies a drop of adhesive to the strip and forces the adhesives bearing side of the strip into contact with the surface of a plastic bag, thus providing an attached bag tie. The apparatus is suitable for use at the output of a bag making machine, means being provided to attach the bag tie to a moving bag in correct register with the bag mouth.

Elmfite @tates Patent 11 1 1111 3,835,755

Jones 1 Sept. 17, 1974 BAG TIE DISPENSER 3,099,237 7/1963 Currin et al.93/35 os x 3,355,995 12/1967 Borkmann et al 93/1 TS [751 invent ElwynJones Bebe, 3,411,418 11/1968 Seragnoli 93/1 TS Quebec, Canada 3,579,3975 1971 Schwarzkopf 93/1 TS ux A ig Canadian Industries Limited 3,773,591ll/l973 Blalt 93/35 H X Montreal, Quebec Canada 3.794545 2/1974 Lucas93/8 WA Filedl 1973 Primary ExaminerRoy Lake 2 APPL 343,451 AssistantExam1'ner.lames F. Coan Attorney, Agent, or Firm-Alexander O. McIntosh[30] Foreign Application Priority Data ABSTRACT Apr. 10, 1972 GreatBr1ta1n l640l/72 An apparatus that cuts a str1p of plast1c t1lm from a52 us. 01 93/8 WA, 93/35 v13, 156/519, length of film advanced y 9 filmmetering device. 9- 5 /57 plies a drop of adhesive to the strip andforces the ad- 51 1m. (:1 B31b 1/90 hesives bearing side of the Stripinto Contact with the [58] Fi ld f s h 93 3 W 3 R, 1 5 35 VL, surface ofa plastic bag, thus providing an attached 93/35 D3 3 5 H; 15 519 573 bagtie. The apparatus is suitable for use at the output of a bag makingmachine, means being provided to at- [5 3 References Cited tach the bagtie to a moving bag in correct register UNITED STATES PATENTS the bag 92,995,174 8/1961 Wang 156/519 8 Claims, 3 Drawing Figures aaa'mssPAIENIED sen 71924 sum 1 ur 2 PAIENIEUSEPITIQYI 3335.155

SHEEI '2 [IF 2 MACH/NE I I 5 I 44 I I I I BAG TIE DISPENSER Thisinvention relates to an apparatus for forming bag ties and for attachingsaid ties to a bag.

Bags are used extensively as containers for a variety of products.Frequently this use requires that the bag be closed by means of a tie.Such ties may be of wire enclosed within paper tape, or be strips offlexible sheet plastic. 1t is usual to include a group of ties with suchbags when they are sold to the public, the ties being enclosed asseparate articles with the package of bags. This is common practice withbags intended for domestic use as containers for food, and also withbags used to handle garbage.

There is a disadvantage is supplying bag ties separately with packagesof bags, since the consumer may lose the set of ties before the bags inthe package are exhausted. There is therefore an advantage in having abag tie attached directly to the bag. However, such a method ofproviding bag ties will require extensive manual labour unless a machinemethod of attaching ties to bags is devised.

The present invention provides an apparatus that forms strips offlexible material and attaches such strips to bags with adhesive inposition appropriate to serve as ties to close the bags.

Therefore, the primary object of this invention is to provide a meansfor the rapid attachment of bag ties to bags. An additional object is toprovide a means for preparing bag ties from plastic sheet material.Further objects will appear hereinafter.

The apparatus of this invention comprises 1. means for providing a stripof flexible material,

2. means for applying a portion of adhesive to the surface of the strip,

3. means for placing the strip with the adhesive carrying surface incontact with the surface of a bag in position for service as a bag tie.

A preferred embodiment of the apparatus of this invention comprises 1.means for cutting a strip from a length of flexible material to form abag tie, said cutting means being located adjacent to a bag supportingmeans,

2. adhesive applicator adapted to apply a portion of adhesive to thesurface of the strip,

3. guide means adapted to guide the strip on to the surface of a bagsupported by the supporting means, and

4. pressing means adapted to press the adhesive carrying surface of thestrip against the bag on the supporting means.

Normally, the adhesive will be applied to the central part of the strip.

The invention is illustrated by way of example in the accompanyingdrawings wherein FIG. 1 is a view, partly diagrammatical, of theapparatus showing a cut strip of material passing between a stripcutting device and a roll carrying the bag to which it will be attached,

FIG. 2 is a side elevation of a strip cutting device, and

FIG. 3 is a schematic diagram of the electricalpneumatic control systemof the apparatus.

Referring to the drawings at l is shown a roll over which is travellinga length of plastic bags 2 joined along transverse lines ofperforations. Roll 1 can conveniently be an element of the bag foldingand stacking machine disclosed in Canadian Pat. application No. 101,336filed on Dec. 22, 1970 in the names of E. D. Jones and D. E. Scuffell(corresponding to British application No. 55494/71). At 3 is shown astrip of plastic film issuing from a strip cutting device showngenerally at 4. The operations of roll 1 and strip cutting device 4 aresynchronized so that strip 3 falls on the length of bags intermediatetwo transverse lines of perforations and adjacent to a bag mouth. At 5is shown a gun adapted to eject a small portion of adhesive onto theunder surface of strip 3. The operation of gun 5 is synchronized withthe operation of cutting device 4 so that the adhesive will land on thecentral part of strip 3. When strip 3 falls on the bag passing over roll1 movable roll 6 is moved into contact with the strip and bag, forcingthe strip into close contact with the bag and making an adhesive bondbetween the two. Roll 6 is then withdrawn.

Strip cutting device 4 functions to cut strips of film from a length ofplastic film. The length of film is shown at 7. A preselected length offilm is metered by rolls 8 and 9. Upper roll 8 is driven intermittentlythrough the action of arm 10 connected to said roll throughunidirectional clutch 11. The outer extremity of arm 10 is linked to thepiston of air cylinder-piston unit 12 through clevis 13, so that theaction of unit 12 drives roll 8. Roll 8 turns in bearings carried byside plates 14 and 15.

To the opposite end of roll 8 is attached ratchet wheel 16. The rotationof 16 is controlled by cooperating pawl 17 pivotted on shaft 18. Pawl 17is lifted out of engagement with ratchet wheel 16 by the action of thepiston of air cylinder-piston unit 19. Pawl 17 is urged into eengagement with ratchet wheel 16 by means of a spring not shown. Thefunction of ratchet wheel 16 and cooperating pawl 17 is to controlreproducibly the amount of film metered by rolls 8 and 9.

Lower roll 9 is mounted in bearings carried at the extremities of arms20. Arms 20 are attached to cross shaft 21 which is joumalled inbearings in side plates 14, 15. To the outer end of shaft 21 is attachedarm 22. The free end of arm 22 is linked to the piston of aircylinder-piston unit 24 through clevis 23 attached to the piston.Through the action of 24 roll 9 is kept in engagement with roll 8 or itcan be lowered so that film 7 may be threaded between the rolls.

The length of film is cut by the action of upper movable knife blade 25and lower fixed knife blade 26. Knife blade 26 is carried by knifesupport 27 which is attached to side plates 14, 15 of the apparatus.Knife blade 25 is carried by knife support 28 which is pivota blymounted at 29 in knife support frame 30. Frame 30 slides vertically,being guided by four rollers 31 mounted in front plate 32, and twopinions 33. The two pinions are carried by cross shaft 34 and mesh withrack bars 35 mounted on frame 30.

The motion of knife frame support 30 and its knife blade 25 is effectedby air cylinder-piston unit 36 which is mounted on top plate 37 of theapparatus. The piston of 36 is linked to clevis 38 carried by the uppercross piece of frame 30. Air cylinder-piston unit 39 is mounted on thelower cross piece of frame 30 with its piston linked to a projection ofpivotted knife support 28. Air cylinder-piston unit 39'functions topress upper knife blade 25 agains lower knife blade 26 during thecutting of the film, thus facilitating the cutting action.

The strip of film cut by knife blades 25 and 26 is guided onto the bagon roll 1 by means of lower guide 40 fixed to side plate 15, and upperguide 41 linked by hinge 42 to said side plate. Upper guide 41 isconnected to knife suport 28 by link 43 which passes through a bore insaid support. A helical spring carried by link 43 urges guide 41downwards. Thus when knife blade 25 moves down, guides 40 and 41 graspone end of the cut strip, causing the other end of the strip to hangdown over roll 1.

The operation of the apparatus is coordinated by a pneumatic-electricalcontrol system as illustrated in FIG. 3. Operation is initiated by apulsed signal from the machine that processes the bags. This may be abag folding and stacking machine. The timing of this pulse issynchronized with the operation of the machine delivering bags to thebag support roll 1 in order to ensure that the bag tie will be attachedto the desired position on the bag, i.e., adjacent to the bag opening.When this signal is received knife blade 25 is in the lower position,having just cut off a strip of film which is held by guides 40 and 41.At this stage of the operating cycle movable roll 6 will be withdrawnfrom contact with roll 1. When the pulsed signal is received it actuatesa first air valve V.l feeding air to air cylinder-piston units 36 and39, causing knife blade 25 to rise, releasing the cut strip 3 fromguides 40 and 41. At the same time the control circuit actuates an aircylinder-piston unit 44 which causes movable roll 6 to press againstroll 1, and adhesive gun is actuated by a pulse from pulse generator 47,ejecting a small amount of adhesive onto the under surface of the cutstrip. The strip carrying the adhesive is then pressed against the bagon roll 1 by the action of roll 6.

When knife blade 25 rises cam operated microswitch 45 is actuatedenergizing the solenoid of air valve V2. Valve V2. then directs air topulser 46, actuating air cylinder-piston unit 19 briefly to cause themomentary lifting of pawl 17 from ratched wheel 16. Air cylinderpistonunit 12 at the same time is actuated by air from V.2 lifting arm andcausing the partial rotation of film metering roll 8. When the camoperating switch 45 passes this switch the switch opens causing thereversal of valve V.2. This causes the arm 10 of roll 8 to return to itsoriginal position, roll 8 remaining fixed in position due to the actionof unidirectional clutch 1 1. The result of these operations is thatfilm equivalent to the width of a bag tie has been advanced between openknife blades and 26.

When the initiating pulsed signal ceases the first air valve V.l isreversed, reversing the air supply to air cylinder-piston units 36 and39 causing knife blade 25 to cut off the strip of film that has beenadvanced between knife blades 25 and 26. The cut off strip is then heldby guides 40 and 41. The first air valve V.1 also feeds air to aircylinder-piston unit 44 controlling the position of movable roll 6,withdrawing this from contact with roll 1. The cycle can now be repeatedupon reception of another initiating signal from the machine processingthe bags.

Air valves V.1 and V.2 are both 4-way solenoid actuated, spring returnvalves.

Controls are provided so that first air valve V.l can be actuatedmanually, permitting manual operation of the apparatus. Also a manuallyoperated air valve is provided to control air cylinder-piston unit 24which controls the position of lower roll 9. The apparatus will also beprovided with a safety guard which is adapted to disable the supply ofair operating knife blade 25. Air of p.s.i.g. pressure is suitable forthe operation of the apparatus.

What we claim is: 1. An Apparatus for forming bag ties and attachingsaid ties to a bag comprising 1. cooperating upper and lower knifeblades adapted to cut a strip from a length of flexible material to forma bag tie,

2. bag supporting means located adjacent to the knife blades,

3. adhesive applicator adapted to apply a portion of adhesive to thesurface of the strip,

4. guide means adapted to grasp the strip when the upper and lower knifeblades are in cutting contact and to guide the cut strip on to thesurface of a bag supported by the bag supporting means, and

5. rotatable roll adapted to be urged toward the bag supporting meansthereby to press the adhesive carrying surface of the strip against thebag supported by the bag supporting means.

2. An apparatus as claimed in claim 1 wherein the upper knife blade ismovable in a vertical sense and is adapted to be actuated by an aircylinder-piston unit.

3. An apparatus as claimed in claim 1 wherein there are providedcooperating upper and lower metering rolls adapted to advance apredetermined length of flexible material between the upper and lowerknife blades in a position to be cut thereby to form a bag tie.

4. An apparatus as claimed in claim 3 wherein there is provided aswitching means adapted to actuate the metering rolls when the upper andlower knife blades are separated.

5. An apparatus as claimed in claim 1 wherein the bag supporting meansis a roll supported for rotation.

6. An apparatus as claimed in claim 1 wherein the ro tatable roll isadapted to be urged toward the bag supporting means through the actionof an air cylinderpiston unit.

7. An apparatus as claimed in claim 1 wherein means are provided toactuate the rotatable roll in synchronisation with the operation of amachine delivering bags to the supporting means so that the bag tie isattached to the bag at a predetermined position.

8. An apparatus as claimed in claim 1 wherein the operation of theapparatus is coordinated by an electricalpneumatic control system.

1. An Apparatus for forming bag ties and attaching said ties to a bagcomprising
 1. cooperating upper and lower knife blades adapted to cut astrip from a length of flexible material to form a bag tie,
 2. bagsupporting means located adjacent to the knife blades,
 3. adhesiveapplicator adapted to apply a portion of adhesive to the surface oF thestrip,
 4. guide means adapted to grasp the strip when the upper andlower knife blades are in cutting contact and to guide the cut strip onto the surface of a bag supported by the bag supporting means, and 5.rotatable roll adapted to be urged toward the bag supporting meansthereby to press the adhesive carrying surface of the strip against thebag supported by the bag supporting means.
 2. bag supporting meanslocated adjacent to the knife blades,
 2. An apparatus as claimed inclaim 1 wherein the upper knife blade is movable in a vertical sense andis adapted to be actuated by an air cylinder-piston unit.
 3. Anapparatus as claimed in claim 1 wherein there are provided cooperatingupper and lower metering rolls adapted to advance a predetermined lengthof flexible material between the upper and lower knife blades in aposition to be cut thereby to form a bag tie.
 3. adhesive applicatoradapted to apply a portion of adhesive to the surface oF the strip, 4.guide means adapted to grasp the strip when the upper and lower knifeblades are in cutting contact and to guide the cut strip on to thesurface of a bag supported by the bag supporting means, and
 4. Anapparatus as claimed in claim 3 wherein there is provided a switchingmeans adapted to actuate the metering rolls when the upper and lowerknife blades are separated.
 5. An apparatus as claimed in claim 1wherein the bag supporting means is a roll supported for rotation. 5.rotatable roll adapted to be urged toward the bag supporting meansthereby to press the adhesive carrying surface of the strip against thebag supported by the bag supporting means.
 6. An apparatus as claimed inclaim 1 wherein the rotatable roll is adapted to be urged toward the bagsupporting means through the action of an air cylinder-piston unit. 7.An apparatus as claimed in claim 1 wherein means are provided to actuatethe rotatable roll in synchronisation with the operation of a machinedelivering bags to the supporting means so that the bag tie is attachedto the bag at a predetermined position.
 8. An apparatus as claimed inclaim 1 wherein the operation of the apparatus is coordinated by anelectrical-pneumatic control system.